As science and technology advance and our living standard improves, many countries enter an aging society, and various health issues of the aging population become a growing concern, and there are numerous patients of neurological diseases and cerebral vascular diseases in the elderly population. For example, a central nervous system damage caused by the factors such as stroke, spinal cord injury, brain dysfunction, and Parkinson's disease may result in patients with varying degrees of limb movement dysfunction. In severe cases, paralysis or hemiplegia may occur. In addition, the number of patients with nerve or limb injuries caused by car accidents becomes increasingly larger. The walking function of the lower extremity is an important index for movement ability and also ensures the necessary conditions of a normal independent life, so that the daily life of most patients of car accidents is affected, and such accidents and injuries definitely bring burdens and challenges to family.
Although most patients of central nervous system damage can recover to an extent of capable of walking independently after surgical or medical treatments, yet after-effects are accompanied. For example, the motion control capability drops, the joints are stiff, and the walking gait is abnormal. As a result, the patient's balance function drops, so as to seriously affect the patient's motion capability and quality of life. Rehabilitation theories and clinical experiments show that correct scientific rehabilitation training has significant effect on the recovery and improvement of the patient's motion capability, in addition to the early surgery and medical treatment. A better recovery can be achieved if the patient takes the rehabilitation training at an early stage after the acute period, wherein the theory of motion rehabilitation therapy bases on the plasticity of our brain, and related medical researches show that although damaged neurons cannot regenerate, yet the lost functions of nerve tissues can be recovered by functional reorganization or compensation. In other words, the brain has the feature of plasticity. Both animal and human tests show that active or passive repetitive training of specific functions of limbs can stimulate proprioceptors and drive the mapping area of central nervous system to have a change and the plasticity of the brain function to occur. However, most of the present rehabilitation therapies rely on a manual method which limits the efficiency and effectiveness of the rehabilitation training, and the equipments of the rehabilitation therapy are relatively simple and unable to meet the patient's rehabilitation requirements.
As robotics advances and the market of rehabilitation therapy expands, the conventional rehabilitation training can be improved. Designing a safe, quantitative, effective and repetitive limb rehabilitation training system becomes an urgent and important issue to modern rehabilitation and treatment, so that rehabilitation robots are introduced and important medical bases are provided. The rehabilitation robot is an important branch of medical robots, and the study of rehabilitation robot integrates different fields including rehabilitation therapy, biomechanics, mechanics, material mechanics, mechanism, electronics, computer science, and robotics. The main difference between rehabilitation robot and industrial robot resides on that the rehabilitation robot acts directly on human body and works with a patient in the same operating space, so that the patient and the rehabilitation robot conduct an overall coordinative motion, and the rehabilitation robot is controlled by a computer and installed with corresponsive sensors and safety systems, and the motion parameters can be adjusted automatically according to the patient's actual needs, so as to achieve the best training. Obviously, the rehabilitation robot can improve the rehabilitation training effect and make the trained motion to be closer to a health condition. In the meantime, the rehabilitation robot also can reduce the laborious training task of a rehabilitation therapist and allow the rehabilitation therapist to spend more efforts on related rehabilitation researches.
In present domestic and foreign researches, the lower extremity drivers of most gait rehabilitation robots adopt a servomotor and a ball screw to convert the rotational motion of the motor into a linear motion in order to drive a link rod mechanism of a power-assisted exoskeleton leg to complete a joint motion, and its features include high-precision position control and easiness of control. However, the deficiencies reside on that most of the power are consumed on the motor and a retardation system, so that the performance is relatively low. Since the motor driving system has a high rigidity and has a relatively large impact to the patient, therefore the patient's leg or other tissues may be injured easily if the system has a sudden change of displacement. Obviously, the rehabilitation training system driven by a motor has less flexibility and lower safety. In addition, the structure of the motor-driven system is more complicated, so that the equipment is large to provide the degree of freedom for the exoskeleton legs.
In view of the aforementioned drawbacks of the prior art, the inventor of the present invention based on years of experiments to conduct extensive researches and experiments, and finally developed a pneumatic lower extremity gait training system in accordance with the present invention to overcome the drawbacks of the prior art.